It is well known that, a mobile terminal (such as a mobile phone, a personal digital assistant (PDA), and so on) generates power consumption during the use, and the battery must be charged if the mobile terminal needs to continue to be used immediately after the power is run out. At present, the mode of charging the mobile terminal is mainly to convert an external power supply into electric energy adapted to the mobile terminal through a charger, so as to charge the mobile terminal. Since there is no suitable external power supply outdoors or in a long journey, the charge is very troublesome. Based on that, people design some mobile charging device, such as, a spring charging device, a solar charging device, and so on. However, all of them have some defects; for example, the spring charging device needs to be wound up manually, and the battery of the mobile terminal still cannot be charged in the case of being not able to perform the manual operation, such as riding or climbing; while the solar charging device has a requirement for the charging environment, the charging efficiency is lower in insufficient light, and especially when the surrounding environment is dark, the battery of the mobile terminal cannot be charged. Thus it is necessary to provide a charging device for a mobile terminal, so as to reduce the impact of external factors on the charging, and to improve the convenience for charging the mobile terminal.